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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
 User Commands                                                 User Commands

                                 2018-05-11



 NAME
      grep, egrep, fgrep - print lines that match patterns

 SYNOPSIS
      grep [OPTION...] PATTERNS [FILE...]
      grep [OPTION...] -e PATTERNS ... [FILE...]
      grep [OPTION...] -f PATTERN_FILE ... [FILE...]

 DESCRIPTION
      grep searches for PATTERNS in each FILE.  PATTERNS is one or patterns
      separated by newline characters, and grep prints each line that
      matches a pattern.

      A FILE of ``-'' stands for standard input.  If no FILE is given,
      recursive searches examine the working directory, and nonrecursive
      searches read standard input.

      In addition, the variant programs egrep and fgrep are the same as
      grep -E and grep -F, respectively.  These variants are deprecated, but
      are provided for backward compatibility.

 OPTIONS
    Generic Program Information
      --help
           Output a usage message and exit.

      -V, --version
           Output the version number of grep and exit.

    Matcher Selection
      -E, --extended-regexp
           Interpret PATTERNS as extended regular expressions (EREs, see
           below).

      -F, --fixed-strings
           Interpret PATTERNS as fixed strings, not regular expressions.

      -G, --basic-regexp
           Interpret PATTERNS as basic regular expressions (BREs, see
           below).  This is the default.

      -P, --perl-regexp
           Interpret PATTERNS as Perl-compatible regular expressions
           (PCREs).  This option is experimental when combined with the -z
           (--null-data) option, and grep -P may warn of unimplemented
           features.

    Matching Control
      -e PATTERNS, --regexp=PATTERNS



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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
 User Commands                                                 User Commands

                                 2018-05-11



           Use PATTERNS as the patterns.  If this option is used multiple
           times or is combined with the -f (--file) option, search for all
           patterns given.  This option can be used to protect a pattern
           beginning with ``-''.

      -f FILE, --file=FILE
           Obtain patterns from FILE, one per line.  If this option is used
           multiple times or is combined with the -e (--regexp) option,
           search for all patterns given.  The empty file contains zero
           patterns, and therefore matches nothing.

      -i, --ignore-case
           Ignore case distinctions, so that characters that differ only in
           case match each other.

      -v, --invert-match
           Invert the sense of matching, to select non-matching lines.

      -w, --word-regexp
           Select only those lines containing matches that form whole words.
           The test is that the matching substring must either be at the
           beginning of the line, or preceded by a non-word constituent
           character.  Similarly, it must be either at the end of the line
           or followed by a non-word constituent character.  Word-
           constituent characters are letters, digits, and the underscore.
           This option has no effect if -x is also specified.

      -x, --line-regexp
           Select only those matches that exactly match the whole line.  For
           a regular expression pattern, this is like parenthesizing the
           pattern and then surrounding it with ^ and $.

      -y   Obsolete synonym for -i.

    General Output Control
      -c, --count
           Suppress normal output; instead print a count of matching lines
           for each input file.  With the -v, --invert-match option (see
           below), count non-matching lines.

      --color[=WHEN], --colour[
           Surround the matched (non-empty) strings, matching lines, context
           lines, file names, line numbers, byte offsets, and separators
           (for fields and groups of context lines) with escape sequences to
           display them in color on the terminal.  The colors are defined by
           the environment variable GREP_COLORS.  The deprecated environment
           variable GREP_COLOR is still supported, but its setting does not
           have priority.  WHEN is never, always, or auto.




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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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      -L, --files-without-match
           Suppress normal output; instead print the name of each input file
           from which no output would normally have been printed.  The
           scanning will stop on the first match.

      -l, --files-with-matches
           Suppress normal output; instead print the name of each input file
           from which output would normally have been printed.  The scanning
           will stop on the first match.

      -m NUM, --max-count=NUM
           Stop reading a file after NUM matching lines.  If the input is
           standard input from a regular file, and NUM matching lines are
           output, grep ensures that the standard input is positioned to
           just after the last matching line before exiting, regardless of
           the presence of trailing context lines.  This enables a calling
           process to resume a search.  When grep stops after NUM matching
           lines, it outputs any trailing context lines.  When the -c or
           --count option is also used, grep does not output a count greater
           than NUM.  When the -v or --invert-match option is also used,
           grep stops after outputting NUM non-matching lines.

      -o, --only-matching
           Print only the matched (non-empty) parts of a matching line, with
           each such part on a separate output line.

      -q, --quiet, --silent
           Quiet; do not write anything to standard output.  Exit
           immediately with zero status if any match is found, even if an
           error was detected.  Also see the -s or --no-messages option.

      -s, --no-messages
           Suppress error messages about nonexistent or unreadable files.

    Output Line Prefix Control
      -b, --byte-offset
           Print the 0-based byte offset within the input file before each
           line of output.  If -o (--only-matching) is specified, print the
           offset of the matching part itself.

      -H, --with-filename
           Print the file name for each match.  This is the default when
           there is more than one file to search.

      -h, --no-filename
           Suppress the prefixing of file names on output.  This is the
           default when there is only one file (or only standard input) to
           search.




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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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                                 2018-05-11



      --label=LABEL
           Display input actually coming from standard input as input coming
           from file LABEL.  This is especially useful when implementing
           tools like zgrep, e.g., gzip -cd foo.gz | grep --label=foo -H
           something.  See also the -H option.

      -n, --line-number
           Prefix each line of output with the 1-based line number within
           its input file.

      -T, --initial-tab
           Make sure that the first character of actual line content lies on
           a tab stop, so that the alignment of tabs looks normal.  This is
           useful with options that prefix their output to the actual
           content: -H,-n, and -b.  In order to improve the probability that
           lines from a single file will all start at the same column, this
           also causes the line number and byte offset (if present) to be
           printed in a minimum size field width.

      -u, --unix-byte-offsets
           Report Unix-style byte offsets.  This switch causes grep to
           report byte offsets as if the file were a Unix-style text file,
           i.e., with CR characters stripped off.  This will produce results
           identical to running grep on a Unix machine.  This option has no
           effect unless -b option is also used; it has no effect on
           platforms other than MS-DOS and MS-Windows.

      -Z, --null
           Output a zero byte (the ASCII NUL character) instead of the
           character that normally follows a file name.  For example, grep
           -lZ outputs a zero byte after each file name instead of the usual
           newline.  This option makes the output unambiguous, even in the
           presence of file names containing unusual characters like
           newlines.  This option can be used with commands like find
           -print0, perl -0, sort -z, and xargs -0 to process arbitrary file
           names, even those that contain newline characters.

    Context Line Control
      -A NUM, --after-context=NUM
           Print NUM lines of trailing context after matching lines.  Places
           a line containing a group separator (--) between contiguous
           groups of matches.  With the -o or --only-matching option, this
           has no effect and a warning is given.

      -B NUM, --before-context=NUM
           Print NUM lines of leading context before matching lines.  Places
           a line containing a group separator (--) between contiguous
           groups of matches.  With the -o or --only-matching option, this
           has no effect and a warning is given.



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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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                                 2018-05-11



      -C NUM, -NUM, --context=NUM
           Print NUM lines of output context.  Places a line containing a
           group separator (--) between contiguous groups of matches.  With
           the -o or --only-matching option, this has no effect and a
           warning is given.

    File and Directory Selection
      -a, --text
           Process a binary file as if it were text; this is equivalent to
           the --binary-files=text option.

      --binary-files=TYPE
           If a file's data or metadata indicate that the file contains
           binary data, assume that the file is of type TYPE.  Non-text
           bytes indicate binary data; these are either output bytes that
           are improperly encoded for the current locale, or null input
           bytes when the -z option is not given.

           By default, TYPE is binary, and when grep discovers that a file
           is binary it suppresses any further output, and instead outputs
           either a one-line message saying that a binary file matches, or
           no message if there is no match.

           If TYPE is without-match, when grep discovers that a file is
           binary it assumes that the rest of the file does not match; this
           is equivalent to the -I option.

           If TYPE is text, grep processes a binary file as if it were text;
           this is equivalent to the -a option.

           When type is binary, grep may treat non-text bytes as line
           terminators even without the -z option.  This means choosing
           binary versus text can affect whether a pattern matches a file.
           For example, when type is binary the pattern q$ might match q
           immediately followed by a null byte, even though this is not
           matched when type is text.  Conversely, when type is binary the
           pattern . (period) might not match a null byte.

           Warning: The -a option might output binary garbage, which can
           have nasty side effects if the output is a terminal and if the
           terminal driver interprets some of it as commands.  On the other
           hand, when reading files whose text encodings are unknown, it can
           be helpful to use -a or to set LC_ALL='C' in the environment, in
           order to find more matches even if the matches are unsafe for
           direct display.

      -D ACTION, --devices=ACTION
           If an input file is a device, FIFO or socket, use ACTION to
           process it.  By default, ACTION is read, which means that devices



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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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                                 2018-05-11



           are read just as if they were ordinary files.  If ACTION is skip,
           devices are silently skipped.

      -d ACTION, --directories=ACTION
           If an input file is a directory, use ACTION to process it.  By
           default, ACTION is read, i.e., read directories just as if they
           were ordinary files.  If ACTION is skip, silently skip
           directories.  If ACTION is recurse, read all files under each
           directory, recursively, following symbolic links only if they are
           on the command line.  This is equivalent to the -r option.

      --exclude=GLOB
           Skip any command-line file with a name suffix that matches the
           pattern GLOB, using wildcard matching; a name suffix is either
           the whole name, or any suffix starting after a / and before a
           non-/.  When searching recursively, skip any subfile whose base
           name matches GLOB; the base name is the part after the last /.  A
           pattern can use *, ?, and [...] as wildcards, and \ to quote a
           wildcard or backslash character literally.

      --exclude-from=FILE
           Skip files whose base name matches any of the file-name globs
           read from FILE (using wildcard matching as described under
           --exclude).

      --exclude-dir=GLOB
           Skip any command-line directory with a name suffix that matches
           the pattern GLOB.  When searching recursively, skip any
           subdirectory whose base name matches GLOB.  Ignore any redundant
           trailing slashes in GLOB.

      -I   Process a binary file as if it did not contain matching data;
           this is equivalent to the --binary-files=without-match option.

      --include=GLOB
           Search only files whose base name matches GLOB (using wildcard
           matching as described under --exclude).

      -r, --recursive
           Read all files under each directory, recursively, following
           symbolic links only if they are on the command line.  Note that
           if no file operand is given, grep searches the working directory.
           This is equivalent to the -d recurse option.

      -R, --dereference-recursive
           Read all files under each directory, recursively.  Follow all
           symbolic links, unlike -r.

    Other Options



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      --line-buffered
           Use line buffering on output.  This can cause a performance
           penalty.

      -U, --binary
           Treat the file(s) as binary.  By default, under MS-DOS and MS-
           Windows, grep guesses whether a file is text or binary as
           described for the --binary-files option.  If grep decides the
           file is a text file, it strips the CR characters from the
           original file contents (to make regular expressions with ^ and $
           work correctly).  Specifying -U overrules this guesswork, causing
           all files to be read and passed to the matching mechanism
           verbatim; if the file is a text file with CR/LF pairs at the end
           of each line, this will cause some regular expressions to fail.
           This option has no effect on platforms other than MS-DOS and MS-
           Windows.

      -z, --null-data
           Treat input and output data as sequences of lines, each
           terminated by a zero byte (the ASCII NUL character) instead of a
           newline.  Like the -Z or --null option, this option can be used
           with commands like sort -z to process arbitrary file names.

 REGULAR EXPRESSIONS
      A regular expression is a pattern that describes a set of strings.
      Regular expressions are constructed analogously to arithmetic
      expressions, by using various operators to combine smaller
      expressions.

      grep understands three different versions of regular expression
      syntax: ``basic'' (BRE), ``extended'' (ERE) and ``perl'' (PCRE).  In
      GNU grep there is no difference in available functionality between
      basic and extended syntaxes.  In other implementations, basic regular
      expressions are less powerful.  The following description applies to
      extended regular expressions; differences for basic regular
      expressions are summarized afterwards.  Perl-compatible regular
      expressions give additional functionality, and are documented in
      pcresyntax(3) and pcrepattern(3), but work only if PCRE is available
      in the system.

      The fundamental building blocks are the regular expressions that match
      a single character.  Most characters, including all letters and
      digits, are regular expressions that match themselves.  Any meta-
      character with special meaning may be quoted by preceding it with a
      backslash.

      The period . matches any single character.  It is unspecified whether
      it matches an encoding error.




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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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                                 2018-05-11



    Character Classes and Bracket Expressions
      A bracket expression is a list of characters enclosed by [ and ].  It
      matches any single character in that list.  If the first character of
      the list is the caret ^ then it matches any character not in the list;
      it is unspecified whether it matches an encoding error.  For example,
      the regular expression [0123456789] matches any single digit.

      Within a bracket expression, a range expression consists of two
      characters separated by a hyphen.  It matches any single character
      that sorts between the two characters, inclusive, using the locale's
      collating sequence and character set.  For example, in the default C
      locale, [a-d] is equivalent to [abcd].  Many locales sort characters
      in dictionary order, and in these locales [a-d] is typically not
      equivalent to [abcd]; it might be equivalent to [aBbCcDd], for
      example.  To obtain the traditional interpretation of bracket
      expressions, you can use the C locale by setting the LC_ALL
      environment variable to the value C.

      Finally, certain named classes of characters are predefined within
      bracket expressions, as follows.  Their names are self explanatory,
      and they are [:alnum:], [:alpha:], [:cntrl:], [:digit:], [:graph:],
      [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:].
      For example, [[:alnum:]] means the character class of numbers and
      letters in the current locale.  In the C locale and ASCII character
      set encoding, this is the same as [0-9A-Za-z].  (Note that the
      brackets in these class names are part of the symbolic names, and must
      be included in addition to the brackets delimiting the bracket
      expression.) Most meta-characters lose their special meaning inside
      bracket expressions.  To include a literal ] place it first in the
      list.  Similarly, to include a literal ^ place it anywhere but first.
      Finally, to include a literal - place it last.

    Anchoring
      The caret ^ and the dollar sign $ are meta-characters that
      respectively match the empty string at the beginning and end of a
      line.

    The Backslash Character and Special Expressions
      The symbols \< and \> respectively match the empty string at the
      beginning and end of a word.  The symbol \b matches the empty string
      at the edge of a word, and \B matches the empty string provided it's
      not at the edge of a word.  The symbol \w is a synonym for
      [_[:alnum:]] and \W is a synonym for [^_[:alnum:]].

    Repetition
      A regular expression may be followed by one of several repetition
      operators:
      ?    The preceding item is optional and matched at most once.
      *    The preceding item will be matched zero or more times.



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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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      +    The preceding item will be matched one or more times.
      {n}  The preceding item is matched exactly n times.
      {n,} The preceding item is matched n or more times.
      {,m} The preceding item is matched at most m times.  This is a GNU
           extension.
      {n,m}
           The preceding item is matched at least n times, but not more than
           m times.

    Concatenation
      Two regular expressions may be concatenated; the resulting regular
      expression matches any string formed by concatenating two substrings
      that respectively match the concatenated expressions.

    Alternation
      Two regular expressions may be joined by the infix operator |; the
      resulting regular expression matches any string matching either
      alternate expression.

    Precedence
      Repetition takes precedence over concatenation, which in turn takes
      precedence over alternation.  A whole expression may be enclosed in
      parentheses to override these precedence rules and form a
      subexpression.

    Back References and Subexpressions
      The back-reference \n, where n is a single digit, matches the
      substring previously matched by the nth parenthesized subexpression of
      the regular expression.

    Basic vs Extended Regular Expressions
      In basic regular expressions the meta-characters ?, +, {, |, (, and )
      lose their special meaning; instead use the backslashed versions \?,
      \+, \{, \|, \(, and \).

 ENVIRONMENT VARIABLES
      The behavior of grep is affected by the following environment
      variables.

      The locale for category LC_foo is specified by examining the three
      environment variables LC_ALL, LC_foo, LANG, in that order.  The first
      of these variables that is set specifies the locale.  For example, if
      LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian
      Portuguese locale is used for the LC_MESSAGES category.  The C locale
      is used if none of these environment variables are set, if the locale
      catalog is not installed, or if grep was not compiled with national
      language support (NLS).  The shell command locale -a lists locales
      that are currently available.




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 GREP(1)                     GNU grep @VERSION@                      GREP(1)
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                                 2018-05-11



      GREP_OPTIONS
           This variable specifies default options to be placed in front of
           any explicit options.  As this causes problems when writing
           portable scripts, this feature will be removed in a future
           release of grep, and grep warns if it is used.  Please use an
           alias or script instead.

      GREP_COLOR
           This variable specifies the color used to highlight matched
           (non-empty) text.  It is deprecated in favor of GREP_COLORS, but
           still supported.  The mt, ms, and mc capabilities of GREP_COLORS
           have priority over it.  It can only specify the color used to
           highlight the matching non-empty text in any matching line (a
           selected line when the -v command-line option is omitted, or a
           context line when -v is specified).  The default is 01;31, which
           means a bold red foreground text on the terminal's default
           background.

      GREP_COLORS
           Specifies the colors and other attributes used to highlight
           various parts of the output.  Its value is a colon-separated list
           of capabilities that defaults to
           ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and
           ne boolean capabilities omitted (i.e., false).  Supported
           capabilities are as follows.

           sl=  SGR substring for whole selected lines (i.e., matching lines
                when the -v command-line option is omitted, or non-matching
                lines when -v is specified).  If however the boolean rv
                capability and the -v command-line option are both
                specified, it applies to context matching lines instead.
                The default is empty (i.e., the terminal's default color
                pair).

           cx=  SGR substring for whole context lines (i.e., non-matching
                lines when the -v command-line option is omitted, or
                matching lines when -v is specified).  If however the
                boolean rv capability and the -v command-line option are
                both specified, it applies to selected non-matching lines
                instead.  The default is empty (i.e., the terminal's default
                color pair).

           rv   Boolean value that reverses (swaps) the meanings of the sl=
                and cx= capabilities when the -v command-line option is
                specified.  The default is false (i.e., the capability is
                omitted).

           mt=01;31
                SGR substring for matching non-empty text in any matching



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                line (i.e., a selected line when the -v command-line option
                is omitted, or a context line when -v is specified).
                Setting this is equivalent to setting both ms= and mc= at
                once to the same value.  The default is a bold red text
                foreground over the current line background.

           ms=01;31
                SGR substring for matching non-empty text in a selected
                line.  (This is only used when the -v command-line option is
                omitted.) The effect of the sl= (or cx= if rv) capability
                remains active when this kicks in.  The default is a bold
                red text foreground over the current line background.

           mc=01;31
                SGR substring for matching non-empty text in a context line.
                (This is only used when the -v command-line option is
                specified.) The effect of the cx= (or sl= if rv) capability
                remains active when this kicks in.  The default is a bold
                red text foreground over the current line background.

           fn=35
                SGR substring for file names prefixing any content line.
                The default is a magenta text foreground over the terminal's
                default background.

           ln=32
                SGR substring for line numbers prefixing any content line.
                The default is a green text foreground over the terminal's
                default background.

           bn=32
                SGR substring for byte offsets prefixing any content line.
                The default is a green text foreground over the terminal's
                default background.

           se=36
                SGR substring for separators that are inserted between
                selected line fields (:), between context line fields, (-),
                and between groups of adjacent lines when nonzero context is
                specified (--).  The default is a cyan text foreground over
                the terminal's default background.

           ne   Boolean value that prevents clearing to the end of line
                using Erase in Line (EL) to Right (\33[K) each time a
                colorized item ends.  This is needed on terminals on which
                EL is not supported.  It is otherwise useful on terminals
                for which the back_color_erase (bce) boolean terminfo
                capability does not apply, when the chosen highlight colors
                do not affect the background, or when EL is too slow or



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                causes too much flicker.  The default is false (i.e., the
                capability is omitted).

           Note that boolean capabilities have no =... part.  They are
           omitted (i.e., false) by default and become true when specified.

           See the Select Graphic Rendition (SGR) section in the
           documentation of the text terminal that is used for permitted
           values and their meaning as character attributes.  These
           substring values are integers in decimal representation and can
           be concatenated with semicolons.  grep takes care of assembling
           the result into a complete SGR sequence (\33[...m).  Common
           values to concatenate include 1 for bold, 4 for underline, 5 for
           blink, 7 for inverse, 39 for default foreground color, 30 to 37
           for foreground colors, 90 to 97 for 16-color mode foreground
           colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes
           foreground colors, 49 for default background color, 40 to 47 for
           background colors, 100 to 107 for 16-color mode background
           colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes
           background colors.

      LC_ALL, LC_COLLATE, LANG
           These variables specify the locale for the LC_COLLATE category,
           which determines the collating sequence used to interpret range
           expressions like [a-z].

      LC_ALL, LC_CTYPE, LANG
           These variables specify the locale for the LC_CTYPE category,
           which determines the type of characters, e.g., which characters
           are whitespace.  This category also determines the character
           encoding, that is, whether text is encoded in UTF-8, ASCII, or
           some other encoding.  In the C or POSIX locale, all characters
           are encoded as a single byte and every byte is a valid character.

      LC_ALL, LC_MESSAGES, LANG
           These variables specify the locale for the LC_MESSAGES category,
           which determines the language that grep uses for messages.  The
           default C locale uses American English messages.

      POSIXLY_CORRECT
           If set, grep behaves as POSIX requires; otherwise, grep behaves
           more like other GNU programs.  POSIX requires that options that
           follow file names must be treated as file names; by default, such
           options are permuted to the front of the operand list and are
           treated as options.  Also, POSIX requires that unrecognized
           options be diagnosed as ``illegal'', but since they are not
           really against the law the default is to diagnose them as
           ``invalid''.  POSIXLY_CORRECT also disables
           _N_GNU_nonoption_argv_flags_, described below.



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      _N_GNU_nonoption_argv_flags_
           (Here N is grep's numeric process ID.)  If the ith character of
           this environment variable's value is 1, do not consider the ith
           operand of grep to be an option, even if it appears to be one.  A
           shell can put this variable in the environment for each command
           it runs, specifying which operands are the results of file name
           wildcard expansion and therefore should not be treated as
           options.  This behavior is available only with the GNU C library,
           and only when POSIXLY_CORRECT is not set.

 EXIT STATUS
      Normally the exit status is 0 if a line is selected, 1 if no lines
      were selected, and 2 if an error occurred.  However, if the -q or
      --quiet or --silent is used and a line is selected, the exit status is
      0 even if an error occurred.

 COPYRIGHT
      Copyright 19982000, 2002, 20052018 Free Software Foundation, Inc.

      This is free software; see the source for copying conditions.  There
      is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
      PARTICULAR PURPOSE.

 BUGS
    Reporting Bugs
      Email bug reports to the bug-reporting address <bug-grep@gnu.org> An
      email archive <https://lists.gnu.org/mailman/listinfo/bug-grep> and a
      bug tracker <https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep>
      are available.

    Known Bugs
      Large repetition counts in the {n,m} construct may cause grep to use
      lots of memory.  In addition, certain other obscure regular expres-
      sions require exponential time and space, and may cause grep to run
      out of memory.

      Back-references are very slow, and may require exponential time.

 SEE ALSO
    Regular Manual Pages
      awk(1), cmp(1), diff(1), find(1), gzip(1), perl(1), sed(1), sort(1),
      xargs(1), zgrep(1), read(2), pcre(3), pcresyntax(3), pcrepattern(3),
      terminfo(5), glob(7), regex(7).

    POSIX Programmer's Manual Page
      grep(1p).

    Full Documentation
      A complete manual <https://www.gnu.org/software/grep/manual/> is



                                   - 13 -          Formatted:  June 18, 2019






 GREP(1)                     GNU grep @VERSION@                      GREP(1)
 User Commands                                                 User Commands

                                 2018-05-11



      available.  If the info and grep programs are properly installed at
      your site, the command

           info grep

      should give you access to the complete manual.

 NOTES
      This man page is maintained only fitfully; the full documentation is
      often more up-to-date.










































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